Compression Ring

[RickWilliams86]

In the process of designing and building some yurts,I helped build a 35 foot Smiley Wood yurts where my friend bought the roof package.
We want to build some smaller one like in the 14 foot size for a friend of his and I would like to put a operable skylight in for ventilation, I am a woodworker and can build this especially because I have access to a CNC router, but wouldn't mind checking out any information as to other people who might of built some.

So if anyone has any suggestions or links I would appreciate it.